This book by Marjorie Grene, available under another title of 'Introduction to Existentialism', provides in a very short space an excellent introduction to the basic thinking of existentialism, a philosophy that has its beginnings in the end of the nineteenth century and the beginning of the twentieth century, and may be considered one of the greatest schools of philosophy for the twentieth century. Grene traces the basics of existentialism by highlighting five key thinkers in the field - Sartre, Heidegger, Kierkegaard, Marcel and Jaspers. Grene states in her introduction to the 1959 edition that she probably needs a chapter on Tillich as well; her conclusion in the text about the incompatibilities of existentialism and Christianity need to be modified in light of his work. 'Existentialism is the philosophy which declares as its first principle that existence is prior to essence.' Kierkegaard and Heidegger both construct a metaphysics along these lines; for many of the existentialist, it leads to a bleak knowledge of the world devoid of values, that some find different ways to escape - Kierkegaard and Marcel go back to concepts of God, whereas others like Sartre carry the despair itself as a primary motif.
Marjorie Glicksman Grene was an American philosopher. She wrote both on existentialism and the philosophy of science, especially the philosophy of biology. She taught at the University of California at Davis from 1965 to 1978 and from 1988 onwards served as the Honorary University Distinguished Professor of philosophy at Virginia Tech.